j 9Q RICHARDSON'S JAGER. 



twelfths in width, then enlarging into an oblong cloaca 10 twelfths in 

 breadth; considerably flattened; the rings 98, unossified, of the same struc- 

 ture as in the Gulls. Bronchi rather wide, of 20 half rings. Muscles as in 

 the Gulls. 



The digestive organs of this bird differ from those of the Gulls only in 

 having the coeca much more elongated; the cloaca oblong, instead of being 

 globular, and the stomach less muscular. The tongue differs greatly from 

 that of either the Gulls or Terns. 



RICHARDSON'S JAGER. 



+Lestris Richardsonii, Swains. 



PLATE CCCCLII.— Male and Young. 



This bird, though rare on the coast of the United States, visits the shores 

 of Massachusetts and Maine, where, during winter, it is seen over the bays 

 and inlets, to which various species of Gulls also resort at the same season. 

 It is more shy and difficult to be approached than the Pomarine Jager. Its 

 flight is rapid and greatly protracted; and, like the other species of this 

 genus, it harasses the smaller Gulls and Terns, forcing them to disgorge their 

 food. Dr. Richardson informs us that it breeds in considerable numbers 

 in the barren grounds, at a distance from the coast, and that it feeds on 

 testaceous mollusca, which are plentiful in the small lakes of the fur 

 countries. I am unable to afford any information respecting its habits; nor 

 can I state decidedly the number of eggs which it lays, although I have 

 procured several of them. They measure two inches and three-eighths in 

 length, by one inch and five-eighths in breadth, are of an oval rather pointed 

 form, and have a dull greyish-yellow ground, patched with umber and faint 

 purple, the markings closer towards the larger end. 



Lestris Richardsonii, Richardson 's Jager, Swains, and Rich. F. Bor. Amer., vol. ii. 



p. 433. 

 Richardson's Jager, Nutt. Man., vol. ii. p. 319. 

 Richardson's Jager, Leslris Richardsonii, Aud. Orn. Bios'., vol. iii. p. 503. 



